Digging deeper on carbon
15 April 2021
Bruce Wood makes no apologies for bringing a mindset created from a lifetime working in the oil and gas industry to livestock production.
Eight years ago, when he entered prime lamb production, Bruce set about developing benchmarks and environmental baselines, production goals, setting up an advisory board and finding the best science to apply to the enterprise.
But Bruce was surprised at how difficult it was to establish the baselines from which to measure environmental and sustainability gains.
"Understanding soil carbon would be a huge improvement for us. We've cracked the nut on many other parameters, but how to measure and get a baseline on soil carbon would really help us to move forward," he said.
Bruce undertook an MLA CN30 carbon accounting workshop to support his endeavours in finding the baseline for his enterprise, as improving soil health and lifting soil carbon were two goals to go hand-in-hand with the business plan for Locmaria Farms.
"On the calculations I've made, if we can double the soil carbon from its current 1.8% in 20 years (while reducing emissions) we should approach being carbon neutral," Bruce said.
Bruce also said he had no interest in generating revenue from carbon neutrality, only in meeting the family's own sustainability goals.
Locmaria Farms is working on simultaneously improving soil health, and is lifting soil carbon and increasing production through various strategies, including by:
Improving grazing systems
In six years of using rotational cell grazing systems, the enterprise has gone from running 2,000 ewes to joining 14,000, and from producing 100kg/ha/year to 300kg/ha/year of meat and wool, with a target of adding another 100kg/ha/year to this bottom line within three years. While increasing production, the goal is to maintain (or possibly further reduce) fertiliser application (superphosphate) at 100kg/ha/year. Bruce suggests cell grazing ensures a more even distribution of manure, reduces nutrient loss, enhances soil health and reduces reliance on synthetic fertiliser.
MLA’s CN30 Manager Margaret Jewell says that the pilot carbon accounting workshops demonstrated to producers that management practices that increase the rate of meat and wool production and/or reduce overall fertiliser inputs can reduce emissions intensity (the volume of emissions produced per kg of liveweight).
Maximising feed efficiency
"The pasture growth curve is our bible. We aim to maximise utilisation instead of allowing pasture to wither and evaporate into the atmosphere at the end of spring," Bruce said.
Rotational cell grazing is used by Locmaria Farms to maximise the amount of grass eaten. In addition, the goal is to cut 2,000 to 3,000 tonnes of dry matter each spring for highly nutritious silage, reducing the reliance on feeding grain in summer and autumn. In addition to helping with business sustainability, maximising feed efficiency and producing silage reduces emissions intensity because they promote increased meat and wool productivity from existing pastures without having to source feed from outside the farm.
To meet its goal of 5% revegetation to native woodlands and grasslands by 2025, Locmaria Farms has already planted more than 10,000 trees. Planting large tree lots was easy, according to Bruce, but maintaining them for maximum growth is the challenge.
"The moment you take stock out you have grass head-high and can't grow trees. This is being overcome by crash grazing tree lots for a few days with large mobs of ewes,” Bruce said.
According to MLA’s CN30 Manager Margaret Jewell trees store carbon, so planting them on farm can offset emissions from animal production, but they also have other benefits as well, such as providing shade and shelter for livestock, which can lead to increased productivity because animals expend less energy maintaining their body temperature.